How to extract pinned notes from a PDF?

We receive a larger number of invoices per PDF. Accounting pins vendor number, account, amount, etc. on each PDF. The challenge for me is now to extract this information from the document.

For the case of there is a better solution, than using the note functionality in PDF, accounting is open to change their process to whatever helps.

I start this new thread as (at least with my key words) this topic seems not to be tackled already. Hope, you can help my with some hints?

Thanks for your help in advance, fzi

use read pdf or read pdf with OCR activities.
And manipulate your data according to what data you want.
Also, you can use the regular expression(REGEX).